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DOUBLE PRECISION FUNCTION DGET06( RCOND, RCONDC )
*
* -- LAPACK test routine (version 3.1) --
* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
* November 2006
*
* .. Scalar Arguments ..
DOUBLE PRECISION RCOND, RCONDC
* ..
*
* Purpose
* =======
*
* DGET06 computes a test ratio to compare two values for RCOND.
*
* Arguments
* ==========
*
* RCOND (input) DOUBLE PRECISION
* The estimate of the reciprocal of the condition number of A,
* as computed by DGECON.
*
* RCONDC (input) DOUBLE PRECISION
* The reciprocal of the condition number of A, computed as
* ( 1/norm(A) ) / norm(inv(A)).
*
* =====================================================================
*
* .. Parameters ..
DOUBLE PRECISION ZERO, ONE
PARAMETER ( ZERO = 0.0D+0, ONE = 1.0D+0 )
* ..
* .. Local Scalars ..
DOUBLE PRECISION EPS, RAT
* ..
* .. External Functions ..
DOUBLE PRECISION DLAMCH
EXTERNAL DLAMCH
* ..
* .. Intrinsic Functions ..
INTRINSIC MAX, MIN
* ..
* .. Executable Statements ..
*
EPS = DLAMCH( 'Epsilon' )
IF( RCOND.GT.ZERO ) THEN
IF( RCONDC.GT.ZERO ) THEN
RAT = MAX( RCOND, RCONDC ) / MIN( RCOND, RCONDC ) -
$ ( ONE-EPS )
ELSE
RAT = RCOND / EPS
END IF
ELSE
IF( RCONDC.GT.ZERO ) THEN
RAT = RCONDC / EPS
ELSE
RAT = ZERO
END IF
END IF
DGET06 = RAT
RETURN
*
* End of DGET06
*
END
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